Crawlspace encapsulation with drain and alarm system

ABSTRACT

A drain and alarm system adapted for use with a crawlspace liner encapsulated crawlspace having a floor is provided. The drain and alarm system has a drainage base arranged to be disposed, at least partially, within a hole of the floor and a drainage cover coupled to the drainage base. The drainage cover has an airtight floor drain and a water activated alarm. The water activated alarm alerts a user of a water leak. The crawlspace liner is sealed to the drainage base or the drainage cover. The crawlspace liner has a drainage cutout allowing liquid to flow from a building side of the crawlspace liner to a floor side of the crawlspace liner through the airtight floor drain.

BACKGROUND

1. Field

The exemplary embodiments disclosed herein relate to a crawlspaceencapsulation system and, more particularly, to a crawlspaceencapsulation with drain and alarm system.

2. Brief Description of Related Developments

Basements or crawlspaces may allow moisture and water vapor, forexample, from dirt or concrete floors, to enter the building structurelocated above the space causing multiple problems, such as insectinfestation or structural problems. A solution exists to provide alining over the inside of the crawl space where the lining provides avapor barrier between the dirt floor or vapor source and the structureto isolate the structure from the high humidity environment. One suchsystem is disclosed in U.S. Pat. No. 6,575,666 which is incorporated byreference herein in its entirety. A problem arises when there is a leak,for example from plumbing, in the building where water or other liquidruns into the liner and is trapped. Accordingly, there is a desire toprovide a drainage and alarm system for lined crawlspaces whereby theuser may be become aware of the leak and whereby the runoff from theleak may be effectively managed.

SUMMARY OF THE EXEMPLARY EMBODIMENTS

In accordance with one exemplary embodiment, a drain and alarm systemadapted for use with a crawlspace liner encapsulated crawlspace having afloor is provided. The drain and alarm system comprises a drainage basearranged to be disposed, at least partially, within a hole of the floorand a drainage cover coupled to the drainage base. The drainage coverhas an airtight floor drain and a water activated alarm. The wateractivated alarm alerts a user of a water leak. The crawlspace liner issealed to the drainage base or the drainage cover. The crawlspace linerhas a drainage cutout allowing liquid to flow from a building side ofthe crawlspace liner to a floor side of the crawlspace liner through theairtight floor drain.

In accordance with another exemplary embodiment, a floor drain systemfor an at least partially subterranean room having a floor is provided.The system comprises a drainage base arranged to be disposed, at leastpartially, within a hole of the floor and an airtight floor draincoupled to the drainage base. Liquid may flow in a first directionthrough the airtight floor drain to the hole in the floor. Air isprevented from flowing through the airtight floor drain in a seconddirection, opposite the first direction.

In accordance with another exemplary embodiment, a floor drain systemfor an at least partially subterranean room having a floor is provided.The system comprises a drainage base having one or more drainage holes,the drainage base arranged to be disposed within a hole of the floor anda drainage cover coupled to the drainage base, the drainage cover havingan airtight floor drain. The drainage cover is provided at an elevationequal to or lower than an elevation of the floor. Liquid may flow in afirst direction through the airtight floor drain to the hole in thefloor. Air is prevented from flowing through the airtight floor drain ina second direction, opposite the first direction.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and other features of the exemplary embodimentsare explained in the following description, taken in connection with theaccompanying drawings, wherein:

FIG. 1 is a side elevation view of a building shown partially incross-section;

FIG. 2 is a section view of the building shown in FIG. 1;

FIG. 3 is an isometric view of a drain and alarm system incorporatingfeatures in accordance with an exemplary embodiment;

FIG. 4 is a section view of the drain and alarm system shown in FIG. 3;and

FIG. 5 is a partial section view of the drain and alarm system shown inFIG. 3.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENT(S)

Referring to FIG. 1, there is shown, side elevation view of a buildingshown partially in cross-section incorporating features in accordancewith an exemplary embodiment. Although the embodiments will be describedwith reference to the embodiments shown in the drawings, it should beunderstood that the present invention can be embodied in many alternateforms of embodiments. In addition, any suitable size, shape or type ofelements or materials could be used.

Referring now to FIG. 1, a building 10 such as a house is illustratedsupported upon peripheral foundation walls 11 such as concrete blockwalls on a peripheral footing 12 buried in the ground beneath the frostline. Also, an access opening 16, shown in FIG. 2, may be provided inthe foundation 11, above ground level. Alternately, a hatch door may beprovided in the roof or ceiling to permit access into the crawlspacewhen necessary. Any air vents present in the crawlspace walls 11 orfoundation may be sealed or covered with a crawlspace liner or otherwiseas air circulation may not be desired after the crawlspace is sealed.Floor 17 of the crawlspace may be poured concrete, or may be a dirtfloor. In alternate embodiments the crawlspace floor may be providedwith an inner peripheral water drainage trench 18 or tile filled withaggregate and may contain a perforated water drainage conduit. Thetrench may open to a sump pit which, depending upon the slope of theterrain, may contain a sump pump (not shown) and a discharge pipe 20(shown in phantom in FIG. 1 and representing the sump pump connectedthereto) which extends up and over the foundation and drains to anexternal location whenever the water level of the sump pit rises to theactivation level of the sump pump. The sump pump may be a conventionallever-activated sump pump. In the exemplary embodiment, a pit or void 19may be formed in the crawlspace floor 17. The pit 19, which may beexcavated through the existing floor may not have a pump or reservoir orpipe 20. Pit 19 may have a drain and alarm system 30 adapted for usewith for example a crawlspace liner 21 encapsulating the crawlspace andsealing floor 17 or other seal barrier sealing the floor.

In the exemplary embodiment shown, the liner 21 extends over and sealsthe crawlspace floor, and may also have portions 21 a extending over andsealing other portions of the crawlspace boundaries, such as thefoundation walls. In alternate embodiments, the liner may have anydesired shape. In still other embodiments, any suitable vapor barriersuch as a sealed concrete floor may be used to encapsulate the chamber.In this embodiment continuous sealed crawlspace liner 21 is provided,such as of plastic film, which may be a monofilm, for example, a 16 milthick durable heavy duty, fiber-reinforced multi-ply plastic film orrubber sheeting. The crawlspace liner 21 may be for example an integralcontinuous durable water barrier film or laminate or may be formed ofwide strips of such film or laminate, such as six feet in width, whichare overlapped and sealed along the edges thereof with the waterproofcaulk or adhesive or adhesive tape to provide a continuous sealedbarrier liner 21 of the required dimensions. The crawlspace liner 21 maybe installed over the dirt floor 17 and over the sump pit 19, ifpresent, and may be extended vertically-upwardly to the tops of thecrawlspace walls. The liner 21 may be sealed against the inner surfaceof the foundation walls 11 peripherally surrounding and enclosing thecrawlspace. The liner 21 may be sufficiently durable to resist tearingand piercing under the weight of the installers. The upper surface ofthe liner may be white in color to brighten the crawlspace. The verticalperipheral crawlspace liner extensions 21 a are extended and supportedagainst the inner surfaces of the foundation walls 11 and sealed theretoat an elevation which is above the exterior ground level, for example,to the tops of the foundation walls. The continuous marginal linerextensions 21 a are sealed or bonded to each other and to the entireperipheral inner wall of the foundation 11 adjacent the top thereof, forexample, by use of an adhesive tape or a continuous bead 21 b ofsuitable adhesive or caulk composition such as a polyurethanecomposition. Nylon fasteners may be used to support the liner 21vertically over the foundation 11 during installation and prior tocaulking. The crawlspace liner 21 and its extended marginal border areas21 a prevent the entry of water vapor from the soil or ground into thecrawlspace environment and prevent external ground water or flood waterentry into the crawlspace and on top of the crawlspace liner 21, overthe dirt floor 17, where it can become trapped and stagnant and cangenerate mold and fungus and water vapor which can deteriorate and rotstructural wood support members of the building 10. Any exterior groundwater which might penetrate the foundation 11, such as through a cementblock wall, is trapped beneath the liner extensions 21 a and flows downinto the dirt floor of the crawl space and into the drain tile channel18, if present. This keeps the head space 15 of the crawlspace, or thecrawlspace environment, dry. Thus, the installed crawlspace liner maytotally encapsulate the crawlspace environment and completely isolatesthe building envelope and upper living spaces from the earth there belowand from the dampness, insects and radon contained therein, to provide ahealthier home environment.

If a leak, for example a plumbing leak, arises from the building thenliquid, such as water, may flow into the crawlspace on top of the linermaterial 21. Without drain and alarm system 30, there generally is noway for water entering from a leak on building side 36 to be expelledand high humidity will result with the attendant problems such as moldgrowth or water fill up of the crawlspace or otherwise. In that case thehomeowner may not be averted to the problem until damage has been done.However, with the drain and alarm system 30, the water or other liquidinside the crawlspace may be diverted from the building side 36 to thefloor side 38 of the barrier 21 and an alarm would notify the homeownerthat there is a problem, such as a plumbing leak for example.Additionally, drain 34 prevents humid air from entering the buildingside 36 of the encapsulation or seal barrier 21 where water can still bedrained in the event of a leak on the building side 36 of liner 21. Aswill be described in greater detail below, drain and alarm system 30 hasa drainage base arranged to be disposed, at least partially, within pitor hole 19 of the floor 17. A drainage cover may be coupled to thedrainage base with the drainage cover having an airtight floor drain 34and a water activated alarm 32. The water activated alarm 32 alerts auser to the presence of for example water or other liquid at the drain34 as will be described. The crawlspace liner 21 may be sealed to thedrainage base or the drainage cover. In the exemplary embodiment, thecrawlspace liner 21 may have a drainage cutout 210 or opening formedtherein allowing liquid to flow from a building side 36 of thecrawlspace liner 21 to a floor side 38 of the crawlspace liner 21through the airtight floor drain 34. In alternate embodiments, where adifferent type of encapsulation barrier is used (e.g. sealed concretefloor) the drainage opening is formed through the encapsulation barrier.The crawlspace liner 21 may be sealed to the air tight drain 34 base,for example, by pinching the crawlspace liner 21 between the drainagecover and the drainage base. In alternate embodiments, any othersuitable sealing devices and methods may be used to seal the liner orbarrier to the drain. In the exemplary embodiment, as noted before thedrain may include optionally a sump pump adapted to pump the liquid (viatube 20) from the drainage base to an exterior of the crawlspace.However, in exemplary embodiments where the drain is placed in a dry pitor void, as may occur for example in a retrofit installation, the drainmay not be provided with a sump pump. The drainage base, in theexemplary embodiment, may also have drainage holes allowing the liquidto drain into the soil. The water activated alarm 32 may be connectedvia suitable interface 40 to a home security system 42 or service 44.The home security system 42 may alert a service 44 over communicationinterface 100, for example phone line 100 or otherwise, such thatservice 44 may alert the homeowner, or plumber or otherwise take actionto resolve the leak. The communication interface 40 may be a wirelessinterface, wired interface or any other suitable communication method.Here, the water activated alarm 32 alerts a user of a water leak fromthe building side 36 of the crawlspace liner 21. As will be describedfurther below, the airtight floor drain may comprise a float and amating stationary valve seat, wherein the float seats against the valveseat forming a substantially airtight seal when there is no flow ofwater from the building side 36 of the crawlspace. In alternateembodiments, any suitable airtight drain may be used.

The drain system may incorporate the drain pit, aggregate-filled draintile and/or sump pit or pump where excessive amounts of water may bedrawn up to the dirt floor 17 of crawlspace and/or may penetrate thecement block foundation 11, above or below ground level, and enter thecrawlspace and accumulate beneath the barrier layer. Further, theincorporation of the drain pit 19 allows water leaking from the buildingside 36 to be effectively drained either into the soil or via a sumppump. The encapsulation liner may provide remediation even in systems inwhich the floor of the crawlspace is formed of poured concrete, whereinwater vapor can penetrate up into the crawlspace at the wall/floorinterface or through cracks in the floor, from the dirt soil therebeneath. Dangerous radon gas from beneath the plastic liner where it canaccumulate by migration up from the sub-soil may also be discharged in acontrolled manner outside the crawlspace and building. For example oneend of a radon-discharge conduit may be extended through the plasticliner 21 and sealed thereto, the other or discharge end being extendedup and over the foundation to the exterior atmosphere for the saferelease of the radon gas. The discharge end of the conduit mayalternately be associated with a continuously-operating fan which drawsthe gas from beneath the plastic liner and out into the atmosphere.Alternatively, the radon discharge conduit can be positioned between thefoundation and the plastic liner from beneath the liner up over thefoundation and out to the discharge end and the exterior atmosphere.

Referring now to FIG. 3, there is shown an isometric view of drain andalarm system 30, incorporated into the chamber encapsulation system,having features in accordance with an exemplary embodiment. Referringalso to FIG. 4, there is shown a section view of the drain and alarmsystem 30 shown in FIG. 3. Referring also to FIG. 5, there is shown apartial section view of the drain and alarm system 30 shown in FIG. 3.As noted before, in the event of an internal leak, for example, aplumbing leak arises from the building, then liquid, such as water, mayflow into the crawlspace on top of the liner material 21. Without drainand alarm system 30, there is no way for water from a leak or otherwiseentering from building side 36 to be expelled and high humidity willresult with the attendant problems previously described. In theexemplary embodiment, the water would be diverted via drain 34 from thebuilding side 36 to the floor side 38 of the barrier 21, the alarm 30would notify the homeowner that there is a problem. Additionally, drain34 prevents humid air from entering the building side 36 of the barrier21.

In the exemplary embodiment shown, the drain and alarm system has adrainage base 44 that may have one or more holes 46, 48. FIGS. 3-5illustrate an exemplary drainage base 44. In alternate embodiments, thebase 44 may have any other suitable shape. The base 44 generally has alower portion 44L with wall(s) shaped to define a void. The wall(s) ofthe lower portion, in the exemplary embodiment shown, form a generallycontinuous wall, though in alternate embodiments the wall(s) may besectioned or spaced to define gaps or spaces (e.g. vertical gaps) in thebase. In this embodiment, the base may be a one piece molding (i.e. ofunitary construction) made of any suitable material such as plastic,etc. In alternate embodiments, the base may include sections (e.g.vertically stackable sections or horizontally mateable sections) thatmay be assembled to form the base. The lower portion of the base may beprovided with sufficient height to define the desired void when placedin pit 19 and surrounded by aggregate 62. In alternate embodiments, thelower portion of base 44 may be provided with a variable length, such asby having an accordion pleat or telescoping sections. As seen in FIG. 4,the lower base portion 44L may have an end lip 44E (defining hole 48)shaped (e.g. substantially “S” shape) to provide increased strength. Thewall(s) of the lower portion 44L have holes 46 formed therein. Thenumber, size and location of the holes 46 shown in FIGS. 3-4 is merelyexemplary, and in alternate embodiments, the lower base portion wall(s)may have any suitable number, size and location of drain holes. As maybe realized, in the case of a dry sump installation, drain holes 46 andin draining the fluid inside the drain base (from drain 34) to thesurrounding aggregate and eventual resorbtion in soil. In the case ofinstallation in a wet sump, holes 46 may serve to allow undergroundliquid to flow into the base drain and to the sump pump (that may belocated inside) for pumping. In the exemplary embodiment shown, the base44 may have a membrane or a flange 88 generally surrounding the top ofthe base. The flange 88 may be of any desired width and shape, forexample 1″ to 3″ in width, and substantially flat as shown, and mayprovide an interface between drain base 44 and surrounding floor 17and/or barrier 21 as will be described below. As seen best in FIG. 5, atransition section may connect the flange 88 (which may be substantiallyhorizontal) to the walls of the lower portion 44L of the base (which maybe substantially vertical). In this embodiment, the transition has asubstantially straight pitched section at a desired incline angle 92(e.g. about 20°), though in alternate embodiments, the transition mayhave any suitable shape. In the exemplary embodiment, the pitchedsection of the transition may form a seating/contact surface for sealingbarrier 21 to the drain as will be described below. A large hole 48 (seeFIG. 4) may be provided at the bottom of drainage base 44 to effectefficient drainage into the soil. The drainage base 44 may be arrangedto be disposed, at least partially, within pit 19 of the floor 17. Inalternate embodiments, drainage base may be placed on a low point offloor 17 or otherwise placed within, below or on floor 17 where the basecan effect drainage from the building side of liner 21. The bottom ofthe base may be seated against the bottom of the pit, or may besuspended a distance from the bottom of pit 19 (such as when flange 33suspends the base from floor 17).

Drainage cover 50 may be coupled to the drainage base 44 with drainagecover 50 having an airtight floor drain 34 that may be coupled todrainage base 44. FIGS. 3-5 show a representative cover 50. Cover 50 isshown fastened to base 44 with screws 82. In alternate embodiments, anysuitable fastening or fabrication could be provided. In other alternateembodiments the drainage cover and base may be molded together orotherwise fabricated. The drainage cover 50 may be provided at anelevation equal to or lower than an elevation of the floor 17. In thisembodiment, base 44 and cover 50 may be installed in pit 19 of dirt orconcrete floor 17 at the lowest point and could be surrounded forexample by crushed stone or any other suitable aggregate. The drainagebase 44 may be installed below the cover 50 to create a void space 60within the soil. Liquid that may be channeled from barrier 21 as will bedescribed below, may flow in a first direction indicated by arrow 54(see FIG. 4) through the airtight floor drain to the pit 19 in the floor17. As will be described further below, air is prevented from flowingthrough the airtight floor drain 34 in a second direction 56, oppositethe first direction 54. The airtight floor drain 34 may be installed ata low point of the floor covered by vapor barrier 21 or otherwise.Liquid flowing in the first direction from the building side 36 may beabsorbed by soil around the pit 19.

As seen in FIGS. 3-4, in this embodiment, the cover 50 is configured sothat an alarm 32 may be installed proximate the airtight floor drain 34,where the alarm 32 alerts a user to the presence of water flowing to thedrain. In alternate embodiments, other suitable locations for alarm 32may be provided, for example on liner 21 proximate drain 34 orotherwise. In this exemplary embodiment, the alarm may be a DC wateractivated alarm 32. The cover 50 may have an alarm receiving pocket 68proximate the airtight floor drain. The airtight floor drain 34, in theexemplary embodiment may have a seat or cup 66 and a ball 64 undergrating 70. In alternate embodiments any other suitable valve may beused to provide the airtight drain in the cover. In other alternateembodiments, the airtight drain may be mounted directly on the drainbase and the cover sealed to the drain. The drain may also have a checkor back flow valve in this embodiment formed by seat or cup 98. Thealarm may have any suitable sensor that detects the presence of water orhigh humidity. Three bosses 90 may be provided in recess 68 to locatethe alarm 32. In alternate embodiments, any suitable method to locatealarm 32 may be provided. Here, alarm 32 may be battery powered orpowered otherwise. In the event alarm 32 is battery powered, a lowbattery alarm may also be provided to alert the homeowner to change thebattery. In the exemplary embodiment, a wall or lip 84, for example, anabout 0.25″ high wall may be provided around most of the opening fordrain 34 to effect sequential flow from alarm to drain as will bedescribed below. In the exemplary embodiment, a dam 86, for example, anabout 0.125″ high dam may be formed between the alarm well 68 and thedrain 34 in this embodiment, the well 68 is at a higher elevation thandrain 34. The dam 68 ensures that water will activate contacts 80 on thealarm before being drained. Dam 86 ensures sufficient water is trappedin recess 68. As seen best in FIG. 3, the alarm well 68 may communicatevia groove 72 with a perimeter channel 72P (see also FIGS. 4-5) thatwater flowing on the barrier 21 towards drain 34 would first encounter.As may be realized, groove 72 directs water collecting at the rim to thealarm well 68 before the water reaches drain 34. This ensures that thealarm is triggered even at low flow rates. Water enters drain 34 bypassing from the leak, to the liner 21 collecting toward the lowpoint/elevation where the drain is located, flows through recess 72P, 72to activate alarm 32 by filling recess 68 up to the level of dam 86,then flows through dam 86 into grating 70 of drain 34. Within drain 34,the floating ball 64 seats in the seat 66 forming a substantiallyairtight seal between the edge of cup 66 and the surface of floatingball 64. Water entering drain 34 from the building side of the drain istrapped until the level of water within drain 34 reaches the matingsurface of cup 66. Here, as the level increases, floating ball 64 floatsand unseats from the seat 66 allowing water to drain through. Similarly,as the water flow is eliminated, the ball will reseat on seat 66creating a substantially airtight seal. Additionally, if the water levelincreases on the floor side of liner 21, drain 34 may be configured toprevent the water from entering to the building side of the barrier 21.Here, water rising will unseat ball 64 from seat 66 and, as it rises,will cause it to seat on inverted seat 98. In the event drainage holes70 are only provided within inverted cup 98, water will be preventedfrom backing through the drain 34.

As noted before, in the embodiment shown, drainage base 44 may beinstalled below the airtight floor drain 34 to create a void space 60within the soil. Additionally, void space 60 may communicate with asection of PVC pipe 13 to further facilitate drainage. The drain issealed to the barrier 21 maintaining the encapsulation of the chamber.As seen best in FIG. 5, the vapor barrier 21 may be pinched between thedrainage cover 50 and the drainage base 44. In alternate embodiments,any suitable method of sealing barrier 21 to drain 34 may be provided.Membrane or flange 88 on base 44 may provide support to barrier 21. Thishelps in avoiding wrinkling of the barrier which may disturb theadequacy of the seal between barrier and drain. A rim 74 may be providedon the bottom side of the cover 50 to capture barrier 21 to the base 44(where barrier 21 has a hole allowing water to pass through drain 34).Thus, if a leak, for example, a plumbing leak arises from the buildingthen liquid, such as water, may flow into the crawlspace on top of theliner material 21 and is directed to air tight drain 34 past alarm 30,and ultimately into void 60 for evaluation. The airtight drain isembedded in the barrier 21 in the floor 17 of the crawlspace withoutviolating the effectiveness of the barrier. Without drain and alarmsystem 30, there is no way for the water to be expelled and highhumidity will result with the attendant problems such as mold growth orwater fill up of the crawlspace or otherwise and the homeowner would notknow of the problem until damage has been done. However, with thepresent drain and alarm combination 30, the water would be diverted fromthe building side 36 to the floor side 38 of the barrier 21 forevaluation and the alarm may notify the homeowner that there is aproblem, (such as the plumbing leak). The alarm water inlet 72P, 72allows a small amount of water to enter the recess 68, where itactivates contacts 80 and sounds the alarm to notify the occupant of theleak possibly at the first instance of the leak. This early alert mayallow the occupant to address the problem before it becomes worse.Additionally, drain 34 prevents humid air from entering the buildingside 36 of the barrier 21.

It should be understood that the foregoing description is onlyillustrative of the invention. Various alternatives and modificationscan be devised by those skilled in the art without departing from theinvention. Accordingly, the present invention is intended to embracethis and all such alternatives, modifications and variances which fallwithin the scope of the appended claims.

1. A crawlspace seal system for sealing at least a partiallysubterranean crawlspace comprising: a seal barrier disposed on at leasta portion of the crawlspace for forming a sealed crawlspace; and a drainsystem communicating with the sealed crawlspace for draining the sealedcrawlspace, the drain system comprising; a drain basin with a drainopening and an inlet, the drain basin being located relative to thesealed crawlspace to collect free flowing liquid on an interior surfaceof the sealed crawlspace, and being disposed at least partially outsidea seal barrier of the sealed crawlspace so that the drain opening isoutside the seal barrier and the inlet is inside the seal barrier andreceives the collecting interior liquid, wherein the inlet is airtightand adapted to allow the collecting liquid to flow from inside the sealbarrier through the inlet to the drain opening outside the seal barrierand prevents air or vapors from outside the seal barrier from enteringthrough the inlet.
 2. The system of claim 1, wherein the drain basin issealed to the seal barrier.
 3. The system of claim 1, wherein the drainbasin is pumpless.
 4. The system of claim 1, wherein the drain openingis underground.
 5. The system of claim 4, further comprising a soil orgravel drywell for accumulating drain liquid from the drain opening. 6.A drain and alarm system adapted for use with a crawlspace linerencapsulated crawlspace having a floor, the drain and alarm systemcomprising: a drainage base arranged to be disposed, at least partially,within a hole of the floor; a drainage cover coupled to the drainagebase, the drainage cover having an airtight floor drain; wherein, thecrawlspace liner is sealed to the drainage base or the drainage cover,and wherein, the airtight floor drain forms a drain passage through thecrawlspace liner allowing liquid to flow from a building side of thecrawlspace liner to outside the crawlspace liner.
 7. The system of claim6, further comprising an alarm activated by liquid entering the drainbase.
 8. The system of claim 6, wherein the drainage base and drainagecover pinch the crawlspace liner between the drainage cover and thedrainage base to seal the liner to the drainage cover.
 9. The system ofclaim 7, wherein the drainage base further comprises a pump adapted topump the liquid from the drainage base to an exterior of the crawlspace.10. The system of claim 6, wherein the drainage base has drainage holesallowing the liquid to drain into the soil.
 11. The system of claim 7,wherein the alarm is connected to a home security system or service. 12.The system of claim 7, wherein the alarm is water activated and alerts auser to presence of water flowing to the drainage base.
 13. The systemof claim 6, wherein the airtight floor drain comprises a floating balland a mating stationary cup, and wherein the floating ball seats in thecup forming a substantially airtight seal.
 14. A floor drain system foran at least partially subterranean room having a floor, the systemcomprising: a drainage base arranged to be disposed, at least partially,within a hole of the floor; an airtight floor drain coupled to thedrainage base; wherein, liquid may flow in a first direction through theairtight floor drain to the hole in the floor, and wherein, air isprevented from flowing through the airtight floor drain in a seconddirection, opposite the first direction.
 15. The floor drain system ofclaim 14, wherein the airtight floor drain is installed at a low pointof the floor, and wherein, the floor has a cover comprising concrete ora vapor barrier, and wherein liquid flowing in the first direction isabsorbed by soil within the hole.
 16. The system of claim 15, whereinthe drainage base is installed below the cover to create a void spacewithin the soil.
 17. The system of claim 14 further comprising an alarminstalled proximate the airtight floor drain, wherein the alarm alerts auser to the presence of water.
 18. The system of claim 15 furthercomprising an alarm installed proximate the airtight floor drain,wherein the alarm alerts a user to the presence of water.
 19. The systemof claim 16 further comprising an alarm installed proximate the airtightfloor drain, wherein the alarm alerts a user to the presence of water.20. The system of claim 16, wherein the drainage base has drainage holesallowing the liquid to drain into the soil.
 21. The system of claim 20,wherein the drainage base is surrounded by stone aggregate.
 22. Thesystem of claim 17, wherein the drainage base has one or more drainageholes.
 23. The system of claim 22, wherein the drainage base issurrounded by stone aggregate.
 24. The system of claim 15, wherein theairtight floor drain comprises a floating ball and a mating stationarycup, and wherein the floating ball seats in the cup forming asubstantially airtight seal.
 25. The system of claim 24 furthercomprising an alarm installed proximate the airtight floor drain,wherein the alarm alerts a user to the presence of water.
 26. The systemof claim 24, wherein the drainage base is installed below the airtightfloor drain to create a void space within the soil.
 27. The system ofclaim 24, wherein the drainage base has one or more drainage holes. 28.The system of claim 25, wherein the drainage base is installed below theairtight floor drain to create a void space within the soil.
 29. Thesystem of claim 28, wherein the drainage base has one or more drainageholes.
 30. The system of claim 29, wherein the drainage base issurrounded by stone aggregate.
 31. The system of claim 16, wherein thevoid space communicates with a section of PVC pipe.
 32. The system ofclaim 31 further comprising an alarm installed proximate the airtightfloor drain, wherein the alarm alerts a user to the presence of water.33. The system of claim 32, wherein the alarm is connected to a homesecurity system or service.
 34. A floor drain system for an at leastpartially subterranean room having a floor, the system comprising: adrainage base having one or more drainage holes, the drainage basearranged so that one or more drainage holes are recessed into soil belowthe floor; a drainage cover coupled to the drainage base, the drainagecover having an airtight floor drain; wherein, the drainage cover isprovided at an elevation equal to or lower than an elevation of thefloor, and wherein, liquid may flow in a first direction through theairtight floor drain to the one or more drainable holes, and wherein,air is prevented from flowing through the airtight floor drain in asecond direction, opposite the first direction.
 35. The system of claim34, wherein the drainage base is surrounded by stone aggregate.
 36. Thesystem of claim 35, wherein a vapor barrier is pinched between thedrainage cover and the drainage base, the vapor barrier being installedon the floor.
 37. The of claim 36 further comprising an alarm installedproximate the drainage cover, wherein the alarm alerts a user to thepresence of water.
 38. The system of claim 37, wherein the drainage baseis surrounded by stone aggregate.
 39. The system of claim 38, whereinthe cover comprises a first recessed area adapted to receive the alarm,and wherein, water flows to the first recessed area before water flowsto the airtight floor drain.